Docking unit for portable computer

ABSTRACT

According to the present invention, provided is a superior docking unit for a portable computer that can provide adequate theft prevention environments for a “single user mode” during which the docking unit is used by only one user, and a “multi-user mode” during which the docking unit is shared by a plurality of users. A docking unit for a portable computer according to the present invention has first and second kensington slots positioned on the outer wall of the main body. When the kensington lock is inserted into the first kensington slot, this event is transmitted to inhibit the release of the engagement of the mounted portable computer, to enable its removal and to restrict the exchange of a PC card relative to the docking unit. But when the kensington lock is inserted into the second kensington slot, this event is not transmitted, so that the mounted portable computer can be removed, and restriction for the exchange of the PC card relative to the docking unit is released. Therefore, in the single user mode, the first kensington lock shall be inserted into the first kensington slot, so that the portable computer and the docking unit can be secured together. In the multi-user mode, the kensington lock shall be inserted into the second kensington slot, so that only the docking unit is secured, the attachment/removal of the portable computer is ensured, and the exchange of the PC card is enabled.

FIELD OF THE INVENTION

[0001] The present invention relates to a docking unit for a portablecomputer on which is mounted a portable computer to expand its variousfunctions, and in particular, relates to a docking unit for a portablecomputer that can adequately prevent the main body of the docking unitand a portable computer mounted thereon from being stolen. Morespecifically, the present invention pertains to a docking unit for aportable computer that provides an adequate security function relativeto the environments in which it is used, in a “single user mode,” duringwhich the docking unit is employed by only one user, and in a“multi-user mode,” during which the docking unit is shared by aplurality of users.

DESCRIPTION OF THE BACKGROUND

[0002] As a consequence of recent technical developments, various typesof personal computers (PC), such as desktop, tower and notebook types,are being manufactured and sold. Generally, desktop and tower computersare designed to be used on desks or tables in offices and in homes;whereas notebook computers, for which portability is a designconsideration, are designed to be operated by batteries in a mobileenvironment.

Notebook PC and Docking Station

[0003] Since it is important that a notebook PC be light and compact,inside one there is no extra space for the installation of expansionadaptor cards and peripheral devices. Further, relying on only a PC cardto provide for the expansion of the periphery of a notebook PC isinadequate. And although portability is an important feature of notebookPCs, it is often necessary for a cable (a printer cable, a monitorcable, or a communication cable) to be connected to and disconnectedfrom a notebook computer between office use and mobile use, so that itsemployment involves some very complicated work and its usability isdeteriorated.

[0004] A “docking station” (also called an “expansion box” or an“expansion unit”) provides for a notebook computer the same workenvironment as that provided by a desktop or a tower PC when thenotebook computer is to be used in an office, while at the same time notdeteriorating from the portability of the notebook PC. The mainfunctions of the docking station are two: “port replication” and “busexpansion.” A port replication is implemented by providing connectionports for a notebook PC on the docking station. That is, if peripheraldevices are connected in advance to the ports on the docking station, auser need only mount his or her notebook PC on the docking station andimmediately can use a printer, an external monitor, an external keyboardand a network. When a user desires to transport a notebook PC, he or sheneed simply remove it from the docking station, leaving all the cablesconnected to the docking station. Since the port replication function ofthe docking station collectively manages the cable connections, thisfunction is also called a “cable management function.” The bus expansionfunction is implemented by the docking station expanding an input/outputbus (or the local bus) of the notebook PC or by providing a bus slot onthe docking station. In other words, while an expansion adaptor card orperipheral devices can not be attached to the notebook PC, these devicescan be used through the docking station. A docking station that providesonly port replication may be called a “port replicator”.

[0005] In FIG. 11 is shown a typically styled notebook PC 100 and adocking station 200. The notebook PC 100 has a docking connector (notshown) on its rear face. The docking connector normally includes severaltens to several hundreds of connector pins. Each connector pin isallocated for a port signal or a bus signal transmitted by the notebookPC 100.

[0006] The docking station 200 comprises a relatively thick main body inwhich electric circuits are incorporated, with thin mounting portion bywhich the notebook PC 100 is mounted at the front of the main body. Aconnector, 101, for joining the docking connector (previously described)to the rear face of the notebook PC 100 is provided at the front of themain body. A cover that can be opened and closed may be provided on thesurface of the docking connector to protect it from a mechanical impactwhen the docking station is not used. A pair of linear protrusions, 102and 103, along which the notebook PC 100 is guided in the attachmentdirection, may be formed on either side edge of the mounting portion.

[0007] The functions and the structure of a docking station are alreadydisclosed in Japanese Patent Applications No. Hei 05-181593 (U.S. Ser.No. 08/276,231, filed Jul. 18, 1994 and now abandoned) and No. Hei06-134124 (U.S. Ser. No. 08/416,398 filed Apr. 6, 1995), both of whichwere assigned to the present assignee.

[0008] The employment styles for the docking station can be classifiedas a “single user mode” and a “multi-user mode.” In the single usermode, only one PC user employs the docking station. In other words, onlyone specific notebook PC is mounted on a docking station. In themulti-user mode, a plurality of PC users employ the docking station incommon. In the multi-user mode, therefore, the notebook PCs of a numberof individual users may alternately be mounted on one docking station.

Security of Notebook PC

[0009] While various electronic apparatuses are made compact and lightand thus are easy to carry, an unwanted side effect of this is thatthefts of the apparatuses have increased. Notebook PCs especially tendto be stolen because their processing capability has been improved andalso because notebook PCs have become popular. Peripheral devices thatare detachably connected to a PC may also be stolen. For example, sincea PC card is a cartridge type and is only as small as a business card,it can easily be stolen. A removable hard disk drive, HDD, may also bestolen because of the data it holds. Therefore, today, the emphasis ison improving office security, i.e., instituting countermeasures toprevent the theft of electronic apparatuses.

[0010] The theft of a notebook PC can be easily prevented by employing aso-called “kensington lock.” The kensington lock, 105 and 107, is usedto inhibit the removal of a notebook PC from a predetermined location byone end of the lock's main body being fixed to an external wall of thecase of the notebook PC (e.g., in FIG. 12, the side of the case shown in(a) or the rear face in (b)), and by securing the cable that extendsfrom the lock's main body at a specific location in an office (e.g., theleg of a desk). The kensington lock is an optional component that issold separately from the notebook PC. A kensington lock sold byKensington Microware Limited can be employed.

[0011]FIG. 13 is a schematic diagram illustrating the assembly of thekensington lock. The kensington lock is constituted by a housing whereina spindle is rotatably provided.

[0012] The spindle has a first portion retained in the housing, and aT-shaped shaft that is fixed to the first portion and projects outwardfrom the housing. The length of the leg of the T-shaped shaft, whichprojects outward from the housing, almost equals the thickness of theexternal wall of the case of the notebook PC (see FIGS. 14(a) and15(a)). The outer size of the head of the T-shaped shaft almost equalsthe inner dimensions of a kensington slot formed in the external wall ofthe notebook PC (see FIGS. 13(c) and (d), and FIG. 14(b)). A pair ofraised contact members are formed at the end of the housing to sandwichthe leg of the shaft. The size in cross section of an assembly of thepair of contact members and the leg of the T-shaped shaft almost equalsthe inner dimensions of the kensington slot formed in the external wallof the notebook PC (see FIGS. 13(c) and (e)). The kensington lock can beinserted into the kensington slot at the shaft rotation position wherethe head of the T-shaped shaft overlaps the contact members.

[0013] A key hole (not shown in FIG. 13) is formed in the other end (thereverse face of the housing) of the spindle. A key that has engaged thekey hole can be rotated, together with the spindle, i.e, the T-shapedshaft, through an angle of 90°. Therefore, by superimposing the head ofthe T-shaped shaft on the outline of the contact members, this assemblycan be inserted into the kensington slot (see FIGS. 14(a) and 14(b)).After the kensington lock is inserted into the kensington slot, the key,116, fitted in the key hole is rotated 90 to inhibit removal of thekensington lock from the kensington slot (see FIGS. 15(a) and 15(b)). Inthis condition, the key is extracted from the key hole, so that thespindle, i.e., the T-shaped shaft can not be rotated, and the kensingtonlock is secured to the external wall of the PC. A tab accepting one endof a cable, 114, is provided on the side of the housing. The other endof the cable (not shown) is secured at a specified location in an office(e.g., to the leg of a desk), so that the PC to which the kensingtonlock is attached can not be carried away.

[0014] The details of the kensington lock are also disclosed in U.S.Pat. No. 5,381,685 (Japanese Unexamined Patent Publication No. Hei06-511297).

Security of Docking Station

[0015] There are two primary purposes of providing security for thedocking station. The first purpose is the security of the dockingstation itself, and the second purpose is the security of a notebook PCmounted on the docking station. For the first purpose, security can beeasily implemented by securing the kensington lock to the main body ofthe docking station, as well as to the main body of the notebook PC.

[0016] For the second purpose, security is not so easily achievedbecause the docking station has two different use styles, the singleuser mode and the multi-user mode, and the applicable security policydiffers for each mode. In the single user mode, the security for boththe docking station and the mounted notebook PC is required, and bothapparatuses should be secured at a predetermined location in the office.In the multi-user mode, although the docking station has to be securedat a predetermined location in the office, a notebook PC should not besecured to the docking station, else shared use of the docking stationby other uses would not be possible.

[0017] A port replicator (Product Model ID No. 46H4219), which isdesigned and produced by IBM Corp. for the notebook computer “IBMThinkPad560 (“ThinkPad” is a trademark of IBM Corp.) sold by IBM Japan,Ltd., interacts with the insertion of the kensington lock into thekensington slot and restricts the operation of the ejection mechanismfor the notebook PC. In short, the notebook PC and the port replicatorare integrally locked. The security mechanism is specifically designedfor use in a single user mode.

[0018] Docking station “Dock,/SelectaDock,” which is designed andproduced by IBM Corp. for the notebook PC “IBM ThinkPad760” sold by IBMJapan, Ltd., includes a kensington slot for securing the dockingstation, and a PC locking mechanism for securing a notebook PC to thedocking station. The kensington lock and the PC locking mechanism can beoperated by individual keys, and the locking mechanism does not interactwith the attachment of the kensington lock. In this case, since a usercan separately select the use for the kensington lock and the locking ofthe notebook PC, a difference between the security policies for thesingle user mode and the multi-user mode can be absorbed. However, auser must be accountable for two different keys and bear moreresponsibility for security.

[0019] In Japanese Unexamined Patent Publications No. Hei 06-124141 andNo. Hei 07-104884, prevention of the theft of an expansion unit is thestated purpose and a technique for locking a notebook PC to theexpansion unit is disclosed. These publications merely provide for thenotebook PC to be secured to the expansion unit for stable employment,and do not take into consideration the use of the expansion unit whenswitching between the single user mode and the multi-user mode isperformed.

[0020] Recently, as was previously described, a notebook PC and adocking station have a PC card slot for inserting a PC card. Sinceplug-and-play is the standard specification for the PC card, a cartridgeform factor is used with which attachment and removal is easy, andaccordingly, PC card theft is easy. The prevention of PC card theft froma notebook PC is recited in, for example, Japanese Patent ApplicationNo. Hei 05-182972 (Japanese Unexamined Patent Publication No. Hei07-44269: our docket No. JA9-93-030), which was assigned to the presentinventor. According to this specification, a curved engagement piece isattached near a PC card exchange opening in the PC main body to preventthe removal of a PC card.

[0021] Since, basically, a PC card inserted into a notebook PC is ownedby a user of a notebook PC, no problem will arise even if a PC cardsecurity mechanism interacts with the security mechanism for the mainbody of the notebook PC. This is rather convenient for the user. Inactuality, however, when a PC card is inserted in the docking station,no determination is made as to whether it is owned by a single user orby multiple users, and the security policy varies in each case.Therefore, the security for a PC card is accompanied by the sameproblems as is the security for the docking station. If the PC cardsecurity mechanism is specifically designed for either a single usermode or a multi-user mode, the security of one of them can not beensured. In addition, if a special locking mechanism is provided foreach mode, the operation will become complex.

[0022] Docking station “Dock,/SelectaDock” (previously described), whichis produced by IBM Corp. for the notebook PC “IBM ThinkPad760” sold byIBM Japan Ltd., has PC card slots, and permits the separate locking ofPC card slots in the notebook PC and in the docking station, so that thedifference between the security policies for the single user mode andthe multi-user mode can be absorbed. As is described above, however, itis required that two security mechanisms be used, so that a user must beaccountable for two different keys.

[0023] The prevention of the theft of a PC card from an expansion unitis not cited in previously described Japanese Unexamined PatentPublications No. Hei 06-124141 and No. Hei 07-104884.

[0024] It is, therefore, one object of the present invention to providea superior docking unit for a portable computer that can effectivelyprevent the theft of the main body of the docking unit and a portablecomputer mounted thereon.

[0025] It is another object of the present invention to provide asuperior docking unit for a portable computer that can provide adequatetheft prevention environments for both a “single user mode”, duringwhich the docking unit is used by only one user, and a “multi-usermode”, during which the docking unit is shared by a plurality of users.

[0026] It is an additional object of the present invention to provide asuperior docking unit for a portable computer that can adequatelyprevent the theft of a portable computer mounted on the docking unit,which is either in a “single user mode” during which the docking unit isused by only one user or a “multi-user mode” during which the dockingunit is shared by a plurality of users.

[0027] It is a further object of the present invention to provide asuperior docking unit for a portable computer that permits the exchangeof a portable computer mounted thereon, while ensuring the security ofthe docking unit and a PC card.

[0028] It is still another object of the present invention to provide asuperior docking unit for a portable computer that can adequatelyprevent the theft of a PC card in both a “single user mode” during whichthe docking unit is used by only one user, and a “multi-user mode”during which the docking unit is shared by a plurality of users.

SUMMARY OF THE PRESENT INVENTION

[0029] To achieve the above objects, according to a first aspect of thepresent invention, a docking unit for mounting a portable computercomprises: (a) a main body; (b) a mounting portion for mounting aportable computer; (c) a first locking portion provided on the outerwall of the main body; (d) a second locking portion provided on theouter wall of the main body; (e) engaging means for engaging with theportable computer mounted on the mounting portion; and (f) engagingcontrol means for controlling the engaging means from being released inresponse to a condition where a locking member, for securing the dockingunit to a desired surrounding object, is loaded either at the firstlocking portion or at the second locking portion.

[0030] According to a second aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a firstkensington slot provided on the outer wall of the main body; (d) asecond kensington slot provided on the outer wall of the main body; (e)engaging means for engaging with the portable computer mounted on themounting portion; and (f) engaging control means for controlling theengaging means from being released in response to whether a kensingtonlock is inserted into the first kensington slot or the second kensingtonslot.

[0031] According to a third aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a firstkensington slot provided on the outer wall of the main body; (d) asecond kensington slot provided on the outer wall of the main body; (e)engaging means for engaging with the portable computer mounted on themounting portion; and (f) engaging control means for inhibiting theengaging means from being released when a kensington lock is insertedinto the first kensington slot, and for not inhibiting the engagingmeans from being released when the kensington lock is inserted into thesecond kensington slot.

[0032] According to a fourth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) ejecting meansprovided for the PC card slot for ejecting an inserted PC card; (e) afirst kensington slot provided on the outer wall of the main body; (f) asecond kensington slot provided on the outer wall of the main body; (g)engaging means for engaging with the portable computer mounted on themounting portion; and (h) engaging control means for inhibiting bothactivation of the ejecting means and release of the engaging means whena kensington lock is inserted into the first kensington slot, and forinhibiting activation of the ejecting means but not inhibiting releaseof the engaging means when the kensington lock is inserted into thesecond kensington slot.

[0033] According to a fifth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a firstkensington slot provided on the outer wall of the main body; (d) asecond kensington slot provided on the outer wall of the main body; (e)engaging means for engaging with the portable computer mounted on themounting portion; (f) engaging release means for releasing the portablecomputer from an engaging with the engaging means; and (g) notificationmeans for inhibiting release of an engaging by notifying the engagingrelease means that a kensington lock has been inserted into the firstkensington slot, and for not notifying the engaging release means thatthe kensington lock has been inserted into the second kensington slot.

[0034] According to a sixth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) restricting meansformed at the ejection opening of the PC card slot to restrict theexchange of a PC card; (e) a first locking portion provided on the outerwall of the main body; (f) a second locking portion provided on theouter wall of the main body; (g) restricting release means for releasinga restriction of the exchange of a PC card imposed by the restrictingmeans; and (h) means for maintaining a restriction condition of theexchange of a PC card in response to whether a locking member, forsecuring the docking unit to a desired peripheral object, is attached tothe first locking portion or the second locking portion.

[0035] According to a seventh aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) restricting meansformed at the ejection opening of the PC card slot to restrict theexchange of a PC card; (e) a first kensington slot provided on the outerwall of the main body; (f) a second kensington slot provided on theouter wall of the main body; (g) restricting release means for releasinga restriction of the exchange of a PC card imposed by the restrictingmeans; and (h) notification means for notifying the restricting releasemeans whether a kensington lock has been inserted into the first or thesecond kensington slot, in order to maintain the restriction conditionof the exchange of a PC card.

[0036] According to an eighth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) restricting meansformed at the ejection opening of the PC card slot to restrict theexchange of a PC card; (e) a first kensington slot provided on the outerwall of the main body, (f) a second kensington slot provided on theouter wall of the main body; (g) engaging means for engaging with theportable computer mounted on the mounting portion; (h) engaging releasemeans for releasing the portable computer from an engaging with theengaging means; (i) restricting release means for releasing arestriction of the exchange of a PC card imposed by the restrictingmeans; (j) first notification means for inhibiting release of anengagement by notifying the engaging release means that a kensingtonlock has been inserted into the first kensington slot, and for notnotifying the engaging release means that the kensington lock has beeninserted into the second kensington slot; and (k) second notificationmeans for maintaining restriction of the exchange of a PC card bynotifying the restricting release means that the kensington lock hasbeen inserted into either the first or the second kensington slot.

[0037] According to a ninth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) ejecting meansprovided for the PC card slot for ejecting an inserted PC card; (e) afirst kensington slot provided on the outer wall of the main body; (f) asecond kensington slot provided on the outer wall of the main body; (g)engaging means for engaging with the portable computer mounted on themounting portion; and (h) engaging control means for inhibiting both anejection of the ejecting means and release of the engaging means when akensington lock is inserted into the first kensington slot, and for notinhibiting neither an ejection of the ejecting means nor release of theengaging means even though the kensington lock is inserted into thesecond kensington slot.

[0038] According to a tenth aspect of the present invention, a dockingunit for mounting a portable computer comprises: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in the main body for inserting a PC card; (d) restricting meansformed at the ejection opening of the PC card slot to restrict theexchange of a PC card; (e) a first kensington slot provided on the outerwall of the main body; (f) a second kensington slot provided on theouter wall of the main body; (g) restricting release means for releasinga restriction of the exchange of a PC card imposed by the restrictingmeans; and (h) notification means for inhibiting release of arestriction by notifying the restricting release means that a kensingtonlock has been inserted into the first kensington slot, and for notnotifying the restricting release means that the kensington lock hasbeen inserted into the second kensington slot.

[0039] According to an eleventh aspect of the present invention, adocking unit for mounting a portable computer comprises: (a) a mainbody; (b) a mounting portion for mounting a portable computer; (c) a PCcard slot provided in the main body for inserting a PC card; (d)restricting means formed at the ejection opening of the PC card slot torestrict the exchange of a PC card; (e) a first kensington slot providedon the outer wall of the main body; (f) a second kensington slotprovided on the outer wall of the main body; (g) engaging means forengaging with the portable computer mounted on the mounting portion; (h)engaging release means for releasing the portable computer from engagingwith the engaging means; (i) restricting release means for releasing arestriction of the exchange of a PC card imposed by the restrictingmeans; (j) first notification means for inhibiting release of anengagement by notifying the engaging release means that a kensingtonlock has been inserted into the first kensington slot, and for notnotifying the engaging release means that the kensington lock has beeninserted into the second kensington slot; and (k) second notificationmeans for inhibiting release of an engagement by notifying the engagingrelease means that a kensington lock has been inserted into the firstkensington slot, and for not notifying the engaging release means thatthe kensington lock has been inserted into the second kensington slot.

[0040] According to a twelfth aspect of the present invention, aportable electronic apparatus comprises: (a) a main body; (b) a firstlocking portion provided on the outer wall of the main body; (c) asecond locking portion provided on the outer wall of the main body; (d)first theft prevention means for setting the main body to a firstsecurity mode when a locking member, for locking the main body to adesired peripheral object, is inserted into the first locking portion;and (e) second theft prevention means for setting the main body to asecond security mode which differs from the first security mode, whenthe locking member is inserted into the second locking portion.

[0041] According to a thirteenth aspect of the present invention, aportable electronic apparatus comprises: (a) a main body; (b) a firstkensington slot provided on the outer wall of the main body; (c) asecond kensington slot provided on the outer wall of the main body; (d)first theft prevention means for setting the main body to a firstsecurity mode when a kensington lock is inserted into the firstkensington slot; and (e) second theft prevention means for setting themain body to a second security mode being different from the firstsecurity mode, when the kensington lock is inserted into the secondkensington slot.

[0042] According to a fourteenth aspect of the present invention, adocking unit for mounting a portable computer comprises: (a) a mainbody; (b) a mounting portion, for mounting a portable computer thereon;(c) a docking connector provided at an elevated location on the mountingportion for an electrical connection with the portable computer on themounting portion; (d) engaging means for engaging with the portablecomputer mounted on the mounting portion; (e) ejecting means, providedon the mounting portion, that can be vertically projected and retracted,and that is vertically projected and raises the portable computermounted on the mounting portion, so that the portable computer can beremoved from the docking connector; (f) ejecting instruction means usedby a user to instruct ejection of the mounted portable computer; (g)notification means for, in response to a user's operation of theejecting instruction means, releasing the engaging means and extendingthe ejecting means upward; and (h) retracting prevention means for, evenafter the user has operated the ejecting instruction means, preventingthe ejecting means when elevated from descending and being retractedinto the mounting portion.

[0043] In a docking unit for a portable computer according to thefourteenth aspect of the present invention, for preventing retraction,sufficient driving force shall be provided for the restrictingprevention means to counter the portable computer's weight. A dockingunit for a portable computer according to the present invention has thefirst and the second kensington slots positioned on the outer wall ofthe main body.

[0044] When the kensington lock is inserted into the first kensingtonslot, this event is transmitted to inhibit the release of the engagingof the mounted portable computer, and to unenable its removal. But whenthe kensington lock is inserted into the second kensington slot, thisevent is not transmitted, so that the mounted portable computer can beremoved. Therefore, in the single user mode, when the kensington lock isinserted into the first kensington slot, the portable computer and thedocking unit can be secured together. In the multi-user mode, when thekensington lock is inserted into the second kensington slot, only thedocking unit is secured, and the attachment and removal of the portablecomputer is ensured. In other words, the docking unit for a portablecomputer of the present invention can absorb the differences in thesecurity policies for the single user mode and the multi-user mode.

[0045] In the docking unit according to the fourth, seventh and eighthaspects, when the kensington lock is inserted into either the first orthe second kensington slots, this event is transmitted to restrict theexchange of a PC card relative to the docking unit. Not only the mainbody of the docking unit and the mounted notebook PC, but also the PCcard are locked, so that the theft of PC cards can be prevented.

[0046] In the docking unit according to the ninth, tenth and eleventhaspects, when the kensington lock is inserted into the first kensingtonslot, this event is transmitted to restrict the exchange of a PC cardrelative to the docking unit. When the kensington lock is inserted intothe second kensington slot, this event is not transmitted, and therestriction concerning the exchange of the PC card relative to thedocking unit is freely released. Therefore, in the single user mode, theexchange of the PC card relative to the docking unit is inhibited byinserting the kensington lock into the first kensington slot, and theftof both the PC card and the docking unit can be prevented. But in themulti-user mode, the exchange of a PC card relative to the docking unitis ensured by the insertion of the kensington lock into the secondkensington slot, and PC cards can be exchanged by the individual users.

[0047] That is, according to the docking unit of the present invention,environments that provide adequate safeguards for the prevention oftheft are provided for the “single user mode”, in which the docking unitis used by only one user, and the “multi-user mode”, in which thedocking unit is shared by a plurality of users. Further, the dockingunit of the present invention can handle the respective securitypolicies for PC cards that differ for the single user mode and for themulti-user mode.

[0048] With the docking unit for a portable computer of the presentinvention, the theft of PC cards can be effectively prevented in theenvironment for the “single user mode”, in which the docking unit isemployed by only a single user and in that for the “multi-user mode”, inwhich the docking unit is employed by a plurality of users.

[0049] In the docking unit according to the fourteenth aspect, there islittle chance that the notebook PC that is ejected upward will bedropped and that the connectors will come into contact. Thus, thechattering that accompanies the contact of the connectors and the damageto data that is due to the chattering can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The other objects, features, and advantages of the presentinvention will become apparent in due course during the detaileddescription of the embodiment of the present invention, which will begiven while referring to the accompanying drawings.

[0051]FIG. 1 is a diagram illustrating outlines of a docking station 10and a notebook PC 50.

[0052]FIG. 2 is a perspective view of the rear face of the dockingstation 10.

[0053]FIG. 3 is a diagram illustrating the internal structure of thedocking station 10, with the edges of a case being represented by brokenlines.

[0054]FIG. 4 is a cross-sectional view of the docking station 10 showingthe movement of a slider 41 correlated with the attachment and removalof the notebook PC 50.

[0055]FIG. 5 is another cross-sectional view of the docking station 10.

[0056]FIG. 6 is the same cross-sectional view as in FIG. 5 for thedocking station 10, and more specifically, shows the condition where astopper plate 46 obstructs the movement of a link 47 when a kensingtonlock is inserted.

[0057]FIG. 7 is a diagram illustrating the internal structure of thedocking station 10, with the edges of the case being represented bybroken lines, and more specifically shows the movement of card shutters23 a and 23 b.

[0058]FIG. 8 is a diagram for explaining a second embodiment of thepresent invention.

[0059]FIG. 9 is a diagram for explaining a third embodiment of thepresent invention, and more specifically, is a diagram illustrating theinternal structure of the docking station 10.

[0060]FIG. 10 is a diagram for explaining the third embodiment, and morespecifically, it is a side view of the docking station 10.

[0061]FIG. 11 is a diagram illustrating a specific style of notebook PC100 and docking station 200.

[0062]FIG. 12 is a diagram showing the condition where a notebook PC islocked by using a kensington lock.

[0063]FIG. 13 is a schematic diagram illustrating the assembly of akensington lock, and more specifically, with FIG. 13(a) being anexploded diagram for the kensington lock, FIG. 13(b) being a diagram forthe assembling of a kensington lock, and FIGS. 13(c),(d) and (e) beingdiagrams for comparing the size and shape of the kensington slot withthe those of the head of a T-shaped shaft, contact members, etc.

[0064]FIG. 14 is a diagram illustrating the condition where thekensington lock is inserted into the outer wall of the PC, and morespecifically with FIG. 14(a) being a side view and FIG. 14(b) being adiagram for the kensington slot viewed from the inside of the PC.

[0065]FIG. 15 is a diagram illustrating the condition where thekensington lock is fixed to the outer wall of the PC, and morespecifically, FIG. 15(a) being a side view and FIG. 15(b) being adiagram for the kensington slot viewed from the inside of the PC.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

[0066]FIG. 1 is a diagram illustrating the outline of a docking station10 and a notebook PC 50 according to the present invention. The dockingstation 10 has a relatively thick main body and a thin mounting portion14 provided at the front of the main body.

[0067] A pair of kensington slots 11 and 12 are formed in a right sidewall of the main body of the docking station 10. The kensington slots 11and 12, which are the same size, can accept a T-shaped shaft of akensington lock (previously described and not shown in FIG. 1). Theprevention of the theft of the docking station 10 can be ensured byinserting a kensington lock into at least one of the kensington slots 11and 12.

[0068] An eject button 13 and a slide knob 17 are provided on the topface of the main body. The eject button 13 is used to disengage themounted notebook PC 50 from the docking station 10 when the notebook PC50 is to be removed. When the eject button 13 is pressed, this action istransmitted to front hooks 15 a, 15 b, 15 c and 15 d, which will bedescribed later. The slide knob 17 is so provided that it slides forwardand backward along an opening formed in the top face of the main body.The movement of the slide knob 17 is transmitted to a mechanism forinhibiting the exchange of a PC card, which will be described later.

[0069] The mounting portion 14 is a table on which the notebook PC 50 ismounted. The hooks 15 a, 15 b, 15 c and 15 d are provided at the fourcorners of the mounting portion 14. The hooks 15 have an L-shaped head,a corner of which is chamfered, and can move 5 mm forward and backward.To mount the notebook PC 50, first, the heads of the-hooks 15 a, 15 b,15 c and 15 d are inserted into engagement holes 55 a, 55 b, 55 c and 55d, which are formed in the bottom of the notebook PC 50. Then, theL-shaped heads of the hooks 15 engage the bottom of the notebook PC 50,so that the units 10 and 50 are joined together. To remove the notebookPC 50 from the docking unit 10, the eject button 13 is pressed torelease the hooks 15 and more than 5 mm forward, so that they aredisengaged from the notebook PC 50, which will be described later. Thenumber of hooks 15 is a design matter determined in accordance with thestrength required to secure the notebook PC 50. Even if only one hook isprovided on each side, instead of two hooks as in the embodiment, thishas no affect on the subject of the present invention.

[0070] A docking connector 16 is provided facing upward for electricconnection with the notebook PC 50. A docking connector 56, whosespecifications match those of the connector 16, is provided facingdownward at a corresponding location in the bottom of the notebook PC50. When the notebook PC 50 is mounted on the mounting portion 14, thedocking connectors 16 and 56 are coupled together to permit the exchangeof electric signals between the units 10 and 50. Although, in thisembodiment, the docking connecters 16 and 56 are constituted by twoconnector rows, this is a design matter determined in accordance withthe number of pins that are provided for the connectors 16 and 56. Thesize and the structure of the connectors 16 and 56 do not directlyaffect the subject of the present invention.

[0071] The top face of the mounting portion 14 is moderately inclined tothe front, so that the keyboard unit of the mounted notebook PC 50 istilted to facilitate typing.

[0072] The notebook PC 50 in FIG. 1 has a so-called “clam shell”structure constituted by a main body which includes a keyboard unit (notshown), and a lid which includes a liquid crystal display (not shown).Inside the case of the notebook PC 50 are provided a system board onwhich are mounted various electronic components, such as a CPU, a memoryand a video controller chip; and peripheral devices, such as a hard diskdrive (HDD) and a floppy disk drive (FDD). The structures and operationsof these electric/electronic components are not directly related to thesubject of the present invention, so that no further explanation forthem will be given in this specification.

[0073]FIG. 2 is a diagram illustrating the rear face of the dockingstation 10. A portion 20 that is raised to the rear is formed on therear face.

[0074] A pair of PC card slots 21 a and 21 b are mounted in the raisedportion 20. Type-cards that conform to the standard developed by PCMCIA(Personal Computer Memory Card International Association)/JEIDA (JapanElectronic Industry Development Association) can be inserted into bothof the slots 21 a or 21 b. A pair of eject buttons 22 a and 22 b areprovided at either end of the raised portion 20 to eject inserted PCcards (not shown). The PC card ejecting mechanism is not directlyrelated to the subject of the present invention, so that no furtherexplanation for it will be given.

[0075] A pair of horizontally retractable card shutters 23 a and 23 b(indicated by the broken lines in FIG. 2) are attached in almost thecenter of the raised portion 20. The movement of the card shutters 23 aand 23 b interacts with the sliding of the slide knob 17 (previouslydescribed). In other words, when the slide knob 17 is moved to the frontof the docking station 10, this movement is transmitted by an internalmechanism (which will be described later) to the card shutters 23 a and23 b, and they are moved to the right and to the left respectively.Since when the card shutters 23 a and 23 b appear they cover at leastpart of the exchange opening of each of the card slots 21 a and 21 b,the exchange of PC cards can be inhibited. As a result, the theft, suchas the stealing of an inserted PC card, or the insertion of a PC card byan unauthorized user who wants to access internal data in the units 10and 50 via the PC card, can be prevented. Although the docking station10 in this embodiment has two PC card slots, the number of card slotsprovided is merely a design matter.

[0076] On the other portions of the rear face of the docking station 10are provided an external mouse port 24, an external keyboard port 25, aMIDI (Musical Instrument Digital Interface)/joystick port, a parallelport 27, a serial port 28, an external FDD port 29, an external CRT(Cathode Ray Tube) port 30, and a line input/output port 31. Forexample, a modem can be connected to the serial port 28, and a printercan be connected to the parallel port 27. Port signals assigned to theconnector pins of the docking connector 16 are transmitted within thedocking station 10 and relayed to the corresponding ports. The types ofports and the number of ports provided for the docking station 10 aredesign matters and are not directly related to the subject of thepresent invention.

[0077] The internal structure of the docking station 10 and theoperational characteristics of its movable portion will now be describedin detail.

[0078] In FIG. 3 is shown the internal structure of the case of thedocking station 10, which is described by chain double-dashed lines. Toavoid complexity in the drawing, components that are not related to thesecurity mechanism are not shown. Peripheral members for supportingmovable portions, or for defining the directions of their movements, arein actuality provided, but are not shown in order to simplify thedrawing.

[0079] A slider 41 has an elongated leg extending to the front, with twohooks 15 a and 15 b integrally formed at and near the end of the leg,and the protrusion 42 integrally formed at its center. The hooks 15 aand 15 b extend outward through openings formed in the upper face of themounting portion 14. A first linear hole 43 and a second linear hole 44are formed at the rear in the slider 41. The linear holes 43 and 44 arelocated at positions that correspond to those of the kensington slots 11and 12, which are formed on the right side wall of the docking station10. Since the widths of the linear holes 43 and 44 are the same as thewidth of the head of the T-shaped shaft of a kensington slot, the headof the T-shaped shaft inserted in either slot 11 or 12 can pass througheither the hole 43 or 44. It should be noted that the length of thefirst linear hole 43 is the same as the head of the T-shaped shaft,while the second linear hole 44 is longer than the head of the T-shapedshaft.

[0080] The slider 41 is so supported by a member (not shown) that it canslide forward and backward. When no kensington lock is inserted intoeither kensington slot 11 or 12, the slider 41 can move forward. When akensington lock is inserted into the kensington slot 12, thecorresponding linear hole 44 has a larger clearance in the forward andbackward direction, and the forward movement of the slider 41 is thuspermitted. When a kensington lock is inserted into the kensington slot11, the corresponding linear hole 43 has almost no clearance in theforward and backward direction, and the forward movement of the slider41 is thus inhibited.

[0081] One end of a coil spring 45 is fixed to the rear portion of theslider 41, and the other end is fixed to the rear wall (not shown) ofthe docking station 10. The slider 41 is constantly retracted by therecovery force exerted by the coil spring 45.

[0082]FIG. 4 is a cross-sectional view of the docking station 10. Thecondition where the slider 41 slides is shown correlated with theattachment and the removal of the notebook PC 50.

[0083] The attachment of the notebook PC 50 will now be explained. Thehooks 15 a and 15 b have L-shaped heads, one corner of which ischamfered. The engagement holes 55 a and 55 b, which are formed in thebottom of the notebook PC 50, have the same internal size as theexternal size of the heads of the hooks 15 a and 15 b, and their frontedges are located 5 mm forward of the hooks 15 a and 15 b. To mount thenotebook PC 50, therefore, first, the heads of the hooks 15 a and 15 bcontact the rear edges of the engagement holes 55 a and 55 b. As thebottom face of the notebook PC 50 descends, the rear edges of theengagement holes 55 a and 55 b slide along the chamfered portions of theheads of the hooks 15 a and 15 b, and the hooks 15 a and 15 b are drivenforward. Accordingly, the slider 41, which is integrally formed with thehooks 15 a and 15 b, is also moved forward against the recovery forceexerted by the coil spring 45 (see the broken line in FIG. 4). When theheads of the hooks 15 a and 15 b are fully inserted through the bottomof the notebook PC 50, the hooks 15 a and 15 b and the slider 41, forwhich obstacles to their rearward movement no longer exist, are returnedto their initial positions. When the L-shaped heads of the hooks 15 aand 15 b contact the rear edges of the engagement holes 55 a and 55 b,the units 10 and 50 are fully engaged.

[0084] The removal of the notebook PC 50 will now be explained. Thebottom of the eject button 13, which is cut off diagonally, contacts thedistal end of the linear protrusion 42, which is integrally formed withthe slider 41. Thus, when the eject button 13 is pressed down, thelinear protrusion 42 is forced forward and slides along the inclinedsurface of the bottom of the eject button 13 (see the broken line inFIG. 4). As a result, the slider 41 and the hooks 15 a and 15 b, whichare integrally formed with the linear protrusion 42, are driven forwardagainst the recovery force exerted by the coil spring 45. Then, thepoint is reached where the bottom wall of the notebook PC 50, which isengaged by the hooks 15 a and 15 b that pass through the engagementholes 55 a and 55 b, is released, so that the notebook PC 50 can beremoved.

[0085] When no kensington lock is inserted into either kensington slot11 or 12, the forward movement of the slider 41 is not restricted, andthe mounted notebook PC 50 can be freely removed. Even when a kensingtonlock is inserted into the kensington slot 12, the slider 41 can moveforward, permitting the mounted notebook PC 50 to be removed, andensuring the implementation of the multi-user mode (the environmentwherein the notebook PCs of a plurality of users can be employed). Onthe other hand, when a kensington lock is inserted into the kensingtonslot 11, the slider 41 can not move forward and the eject button 13 cannot be depressed, so that the hooks 15 a, 15 b, 15 c and 15 d can not bereleased from the engagement holes 55 a, 55 b, 55 c and 55 d. As aresult, since the removal of the notebook PC 50 is inhibited and thedocking station 10 and the notebook PC 50 are securely held together,the physical security inherent to the single user mode is provided.

[0086] Although not shown, the slider 41 and the coil spring 45 aresymmetrically depicted also on the left side of the docking station 10.The depression of the eject button 13 is also transmitted to the slider41 on the left side by a transmission mechanism (not shown). It shouldbe noted that since no kensington slots are formed in the left side wallof the docking station 10, liner holes 43 and 44 are not required forthe left slider 41.

[0087] Referring back to FIG. 3, a stopper plate 46 is a bent member,and shafts 46 a and 46 b project outward from the ends at the curvedportion. These shafts 46 a and 46 b are supported by a support member(not shown) and rotate in the directions indicated by an arrow A.

[0088]FIGS. 5 and 6 are cross sectional views of another docking station10. The positional relationship of the stopper plate 46 and the slider41 should be understood. The stopper plate 46 is located inside theslider 41. When the kensington lock is inserted into either thekensington slot 11 or 12, the head of the T-shaped shaft passes througheither linear hole 43 or 44 of the slider 41, and contacts the sideportion of the stopper plate 46, which is then rotated clockwise in FIG.6 (in a direction indicated by an arrow A). As a result, the upper faceof the stopper plate 46 is elevated from its initial horizontalposition.

[0089] Referring again to FIG. 3, a link 47 is a thin plate in anarrowhead shape. Its distal end is supported at the upper wall of thedocking, station 10 by a shaft 48 so that it can be rotated in thedirection indicated by an arrow C. The previously described slide knob17 is integrally formed with the upper face of the link 47. The slideknob 17 is exposed from above and extends upward into a rectangularopening that is formed on the upper face of the docking station 10, andcan be slid in the longitudinal direction of the opening, i.e., in thedirection indicated by an arrow B. When the slide knob 17 is slid to therear, the link 47 is moved in the direction indicated by the arrow C.

[0090] The leg of the link 47 extends over to the right side of the mainbody of the docking station 10. When a kensington lock has been insertedinto either the kensington slot 11 or 12, and the stopper plate 46 isrotated in the direction indicated by the arrow A, the movement of theleg of the link 47 is obstructed by the upper face of the stopper plate46 (see FIG. 6), and forward movement of the link 47 and the slide knob17 is inhibited.

[0091] The card shutter 23 is formed below the link 47. The card shutter23 is a U-shaped metal plate, the center portion 23′ of which is fixedto the upper wall of the docking station 10. Portions 23 a and 23 b,which are bent outward from the U-shape, are formed at the ends of thelegs of the U-shaped card shutter 23. As is explained while referring toFIG. 2, the bent portions 23 a and 23 b are used to cover the exchangeopenings of the PC card slots 21 a and 21 b.

[0092] A pair of bent portions extend outward from the upper edge in thecenter of the legs of the card shutter 23. Linear cam slits 49 a and 49b are formed in the respective bent portions and approach each other asthey go to the rear. A pair of small protrusions 47 a and 47 b, whichare formed on the lower face of the link 47, engage the cam slits 49 aand 49 b. Since the gap between the small protrusions 47 a and 47 b isconstant, the cam slits 49 a and 49 b are forced to maintain the samegap in accordance with the location to which the slide knob 17, i.e.,the link 47, is moved forward and backward.

[0093] When the slide knob 17 is moved to the frontmost position, andthe small protrusions 47 a and 47 b, which engage the cam slits 49 a and49 b is the greatest, as is shown in FIG. 3, the U-shaped legs of thecard shutter 23 are closed. As a result, the bent portions 23 a and 23 bapproach the center, the exchange openings of the PC card slots 21 a and21 b are fully opened, and the exchange of PC cards can be performed. Inshort, the movement of the slide knob 17 to the front permits thedeactivation of the physical security for the PC card slots 21 a and 21b.

[0094] When the slide knob 17 is moved to the rearmost position, and thesmall protrusions 47 a and 47 b, which engage the cam slits 49 a and 49b, reach the point where the gap between the cam slits 49 a and 49 b isthe smallest, as is shown in FIG. 7, the U-shaped legs of the cardshutter 23 are opened. As a result, the bent portions 23 a and 23 bappear and cover at least part of the exchange openings for the PC cardslots 21 a and 21 b, and the exchange of the PC cards is inhibited. Thetheft of an inserted PC card in the slot 21 a or 21 b by extracting itwithout permission, or the insertion of a PC card by an unauthorizeduser to access information available in the units 10 and 50, can beprevented. In short, the rearward movement of the slide knob 17 permitsthe activation of the physical security for the PC card slots 21 a and21 b.

[0095] From the point of view of the physical security, preferably, thecard shutter 23 is made of relatively hard material, such as carbonsteel, that is difficult to deform.

[0096] The security mechanism in the first embodiment will now bedescribed. As was previously described, the docking station 10 has thetwo kensington slots 11 and 12.

[0097] (1) When the Kensington Lock is Inserted into the Kensington Slot11.

[0098] The docking station 10 is secured at a predetermined position inan office, and its physical security is ensured. Since the operation ofthe eject button 13 is disabled, and the hooks 15 a, 15 b, 15 c and 15 dcan not be released from the engagement holes 55 a, 55 b, 55 c and 55 d,the mounted notebook PC 50 is securely held to the docking station 10.That is, the physical security inherent to the single user mode, duringwhich only one user employs the docking station 10, is provided.

[0099] In this condition, the link 47 is temporarily moved to the rear,in accordance with the movement of the slide knob 17, and can not bereturned to the front because its movement is obstructed by the stopperplate 46 (see FIG. 6). Thus, the bent portions 23 a and 23 b of the cardshutter 23 are exposed, and the exchange of PC cards is inhibited.

[0100] (2) When the Kensington Lock is Inserted into the Kensington Slot12.

[0101] The docking station 10 is secured at a predetermined location inan office, and its physical security is ensured. Since the operation ofthe eject button 13 is enabled, the mounted notebook PC 50 can beremoved from the docking station 10 and can be replaced with anothernotebook PC. In other words, the physical security inherent to themulti-user mode, during which a plurality of PC users share the dockingstation 10, is provided.

[0102] In this condition, the link 47 is temporarily moved to the rear,in accordance with the movement of the slide knob 17, and can not bereturned to the front because its movement is obstructed by the stopperplate 46 (see FIG. 6) Thus, the bent portions 23 a and 23 b of the cardshutter 23 are exposed, and the exchange of PC cards is inhibited.

Second Embodiment

[0103] The difference between the first and the second embodiments isthat the definition of the physical security provided in the multi-usermode is different.

[0104]FIG. 8 is a diagram illustrating the internal structure of adocking station 10 according to a second embodiment of the presentinvention. The arrangement in FIG. 8 differs from that in FIG. 7 in thata linear slit 46 a is formed in a stopper plate 46. The linear slit 46 ais so formed that it has the same shape and size as the first kensingtonslot 11 at a position corresponding to the second kensington slot 12.

[0105] When a kensington lock is inserted into the second kensingtonslot 12, the head of the T-shaped shaft of the kensington lock passesnot only through a second linear slit 44, but also through the linearslit 46 a, and a stopper plate 46 is not rotated in the directionindicated by the arrow A in FIG. 6. Therefore, in this condition, therelease of the card shutter 23 is permitted.

[0106] More specifically, when a kensington lock is inserted into thekensington slot 12, the exchange of notebook PCs and the exchange of PCcards are still enabled though the docking station 10 is secured at apredetermined location in an office. That is, the multi-user mode in thesecond embodiment permits the shared use of the PC card slots 21 of thedocking station 10.

[0107] When the kensington lock is inserted into the first kensingtonslot 11, the same physical security as that provided in the firstembodiment is enabled. In other words, the docking station 10, thenotebook PC 50, and the PC card slot 21 are locked, and this arrangementis used by a single user.

[0108] Third Embodiment:

[0109] The feature of a third embodiment is not a security mechanism,i.e., a locking mechanism, but an ejecting mechanism for a mountednotebook PC. The locking mechanism in this embodiment is equivalent tothat in the first or the second embodiment, so that no detailedexplanation of it will be given.

[0110]FIG. 9 is a diagram illustrating the internal structure of adocking station 10 according to the third embodiment. The lockingmechanism, i.e., the structures of a slider 41, a stopper plate 46, alink 47 and a card shutter 23, and its operational characteristics arethe same as those for corresponding components in the first embodiment.

[0111] When an eject button 13 (not shown in FIG. 9) provided on theupper face of the docking station 10 is depressed, a force exerted inthe direction indicated by an arrow P is applied to a cam 62.

[0112] The cam 62 is fixed to one end of a link bar 61 that is supportedrotatably. When a kensington lock is not inserted into either slot 11 or12, depression force P applied to the eject button 13 is changed to arotational force for rotating the link bar 61 in the direction indicatedby an arrow Q. A pair of cams 63 a and 63 b are integrally formed ateither end of the link bar 61. The rotation force Q is transmittedequally to both sides by the link bar 61 and to the cams 63 a and 63 b.

[0113] Each of the cams 63 a and 63 b has a bent portion at its distalend. When the cams 63 a and 63 b are driven in the direction indicatedby the arrow Q, these bent portions are brought into contact with theends of ejectors 64 a and 64 b.

[0114] The ejectors 64 a and 64 b are U-shaped products that have aprotrusion on either end. A pair of shafts are projected to either sideat the center of each of the ejectors 64 a and 64 b. These shafts aresupported rotatably by a support member (not shown). The protrusions onthe ends of the ejectors 64 a and 64 b contact the bent portions of thecams 63 a and 63 b, as was previously described. The protrusions on theother ends project upward through openings formed in a mounting portion14, so that the protrusions can be projected and retracted. When theeject button 13 is depressed, the rotational force exerted in thedirection indicated by an arrow R is applied to the ejectors 64 a and 64b. As a result, the protrusions on the opposite ends of the ejectors 64a and 64 b are projected outward, and push against the bottom face ofthe mounted notebook PC 50, which is then disengaged from the connectors16 and ejected.

[0115] When the depression of the eject button 13 is halted, therotational force R received from the cams 63 a and 63 b is removed. Inthis embodiment, however, since the lower portion at the other ends ofthe ejectors 64 a and 64 b are supported by leaf springs 65 a and 65 b,the rotational force R for the ejectors 64 a and 64 b is maintained to adegree. Thus, the ejected notebook PC is prevented from dropping back onto the mounting portion 14 (see FIG. 10).

[0116] As is shown in FIG. 11, when the notebook PC is horizontallyattached to or detached from the docking station, the notebook PC, afterit is ejected, remains at the position on the mounting surface at whichit was ejected. However, if, as in this embodiment, the notebook PC isvertically attached to and detached from the docking station, and thedocking connector 16 is provided facing upward, after the notebook PC isejected its own weight may cause it to drop down and produce an unstableelectrical contact condition between the connectors. According to thethird embodiment, since the ejectors 64 a and 64 b are supported by theleaf springs 65 a and 65 b, and the notebook PC can not easily fall, thedocking connectors, once separated from each other will not erroneouslybe brought into contact. As a result, the chattering that accompaniesthe contact of the connectors, and the damage to data due to thechattering can be prevented.

[0117] The present invention has been described in detail whilereferring to a specific embodiment. However, it should be obvious to onehaving ordinary skill in the art that various modifications or revisionsof the embodiment are possible within the scope of the presentinvention. That is, although the present invention has been disclosed byusing an example, it should not be limited to that example. To fullyunderstand the subject of the present invention, the claims should bereferred to.

[0118] As is described above, according to the present invention,provided is a superior docking unit for a portable computer that caneffectively prevent the theft of the main body of the docking unit and aportable computer mounted thereon.

[0119] Further, according to the present invention, provided is asuperior docking unit for a portable computer that can provide adequatetheft prevention environments for a “single user mode” during which thedocking unit is used by only one user, and a “multi-user mode” duringwhich the docking unit is shared by a plurality of users.

[0120] In addition, according to the present invention, provided is asuperior docking unit for a portable computer that can adequatelyprevent the theft of a portable computer mounted on the docking unit,which is either in a “single user mode” during which the docking unit isused by only one user or a “multi-user mode” during which the dockingunit is shared by a plurality of users.

[0121] In addition, according to the present invention, provided is asuperior docking unit for a portable computer that permits the exchangeof a portable computer mounted thereon, while ensuring the security ofthe docking unit and a PC card.

[0122] Still further, according to the present invention, provided is asuperior docking unit for a portable computer that can adequatelyprevent the theft of a PC card in both a “single user mode”, duringwhich the docking unit is used by only one user, and a “multi-usermode”, during which the docking unit is shared by a plurality of users.

What is claimed is:
 1. A docking unit for mounting a portable computercomprising: (a) a main body; (b) a mounting portion for mounting aportable computer; (c) a first locking portion provided on the outerwall of said main body; (d) a second locking portion provided on theouter wall of said main body; (e) engaging means for engaging with theportable computer mounted on said mounting portion; and (f) engagingcontrol means for controlling said engaging means from being released inresponse to a condition where a locking member, for securing saiddocking unit to a desired surrounding object, is loaded at one of saidlocking portions.
 2. A docking unit for mounting a portable computercomprising: (a) a main body; (b) a mounting portion for mounting aportable computer; (c) a first kensington slot provided on the outerwall of said main body; (d) a second kensington slot provided on theouter wall of said main body; (e) engaging means for engaging with theportable computer mounted on said mounting portion; and (f) engagingcontrol means for controlling said engaging means from being released inresponse to whether a kensington lock is inserted into one of said firstand said second kensington slots.
 3. A docking unit for mounting aportable computer comprising: (a) a main body; (b) a mounting portionfor mounting a portable computer; (c) a first kensington slot providedon the outer wall of said-main body; (d) a second kensington slotprovided on the outer wall of said main body; (e) engaging means forengaging with the portable computer mounted on said mounting portion;and (f) engaging control means for inhibiting said engaging means frombeing released in response to that a kensington lock is inserted intosaid first kensington slot, and for not inhibiting said engaging meansfrom being released in response to that the kensington lock is insertedinto said second kensington slot.
 4. A docking unit for mounting aportable computer comprising: (a) a main body; (b) a mounting portionfor mounting a portable computer; (c) a PC card slot provided in saidmain body for inserting a PC card; (d) ejecting means provided for saidPC card slot for ejecting an inserted PC card; (e) a first kensingtonslot provided on the outer wall of said main body; (f) a secondkensington slot provided on the outer wall of said main body; (g)engaging means for engaging with the portable computer mounted on saidmounting portion; and (h) engaging control means for inhibitingactivation of said ejecting means and release of said engaging meanswhen a kensington lock is inserted into said first kensington slot, andfor inhibiting activation of said ejecting means but not inhibitingrelease of said engaging means when the kensington lock is inserted intosaid second kensington slot.
 5. A docking unit for mounting a portablecomputer comprising: (a) a main body; (b) a mounting portion formounting a portable computer; (c) a first kensington slot provided onthe outer wall of said main body; (d) a second kensington slot providedon the outer wall of said main body; (e) engaging means for engagingwith the portable computer mounted on said mounting portion; (f)engaging release means for releasing said portable computer from anengaging with said engaging means; and (g) notification means forinhibiting release of an engaging by notifying said engaging releasemeans that a kensington lock has been inserted into said firstkensington slot, and for not notifying said engaging release means thatsaid kensington lock has been inserted into said second kensington slot.6. A docking unit for mounting a portable computer comprising: (a) amain body; (b) a mounting portion for mounting a portable computer; (c)a PC card slot provided in said main body for inserting a PC card; (d)restricting means formed at said ejection opening of said PC card slotto restrict the exchange of a PC card; (e) a first locking portionprovided on the outer wall of said main body; (f) a second lockingportion provided on the outer wall of said main body; (g) restrictingrelease means for releasing a restriction of the exchange of a PC cardimposed by said restricting means; and (h) means for maintaining arestriction condition on the exchange of a PC card in response towhether a locking member, for securing said docking unit to a desiredperipheral object, is attached at one of said first and said secondlocking portions.
 7. A docking unit for mounting a portable computercomprising: (a) a main body; (b) a mounting portion for mounting aportable computer; (c) a PC card slot provided in said main body forinserting a PC card; (d) restricting means formed at the ejectionopening of said PC card slot to restrict the exchange of a PC card; (e)a first kensington slot provided on the outer wall of said main body;(f) a second kensington slot provided on the outer wall of said mainbody; (g) restricting release means for releasing a restriction of theexchange of a PC card imposed by said restricting means; and (h)notification means for notifying said restricting release means when akensington lock has been inserted into one of said first and said secondkensington slots, in order to maintain said restriction condition of theexchange of a PC card.
 8. A docking unit for mounting a portablecomputer comprising: (a) a main body; (b) a mounting portion formounting a portable computer; (c) a PC card slot provided in said mainbody for inserting a PC card; (d) restricting means formed at theejection opening of said PC card slot to restrict the exchange of a PCcard; (e) a first kensington slot provided on the outer wall of saidmain body; (f) a second kensington slot provided on the outer wall ofsaid main body; (g) engaging means for engaging with the portablecomputer mounted on said mounting portion; (h) engaging release meansfor releasing said portable computer from an engaging with said engagingmeans; (i) restricting release means for releasing a restriction of theexchange of a PC card imposed by said restricting means; (j) firstnotification means for inhibiting release of an engagement by notifyingsaid engaging release means that a kensington lock has been insertedinto said first kensington slot, and for not notifying said engagingrelease means that said kensington lock has been inserted into saidsecond kensington slot; and (k) second notification means formaintaining restriction of the exchange of a PC card by notifying saidrestricting release means that said kensington lock has been insertedinto one of said first and said second kensington slots.
 9. A dockingunit for mounting a portable computer comprising: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in said main body for inserting a PC card; (d) ejecting meansprovided for said PC card slot for ejecting an inserted PC card; (e) afirst kensington slot provided on the outer wall of said main body; (f)a second kensington slot provided on the outer wall of said main body;(g) engaging means for engaging with the portable computer mounted onsaid mounting portion; and (h) engaging control means for inhibitingboth an ejection of said ejecting means and release of said engagingmeans when a kensington lock is inserted into said first kensingtonslot, and for not inhibiting either an ejection of said ejecting meansnor release of said engaging means even though said kensington lock isinserted into said second kensington slot.
 10. A docking unit formounting a portable computer comprising: (a) a main body; (b) a mountingportion for mounting a portable computer; (c) a PC card slot provided insaid main body for inserting a PC card; (d) restricting means formed atsaid ejection opening of said PC card slot to restrict the exchange of aPC card; (e) a first kensington slot provided on the outer wall of saidmain body; (f) a second kensington slot provided on the outer wall ofsaid main body; (g) restricting release means for releasing arestriction of the exchange of a PC card imposed by said restrictingmeans; and (h) notification means for inhibiting release of arestriction by notifying said restricting release means that akensington lock has been inserted into said first kensington slot, andfor not notifying said restricting release means that said kensingtonlock has been inserted into said second kensington slot.
 11. A dockingunit for mounting a portable computer comprising: (a) a main body; (b) amounting portion for mounting a portable computer; (c) a PC card slotprovided in said main body for inserting a PC card; (d) restrictingmeans formed at said ejection opening of said PC card slot to restrictthe exchange of a PC card; (e) a first kensington slot provided on theouter wall of said main body; (f) a second kensington slot provided onthe outer wall of said main body; (g) engaging means for engaging withthe portable computer mounted on said mounting portion; (h) engagingrelease means for releasing said portable computer from an engaging withsaid engaging means; (i) restricting release means for releasing arestriction of the exchange of a PC card imposed by said restrictingmeans; (j) first notification means for inhibiting release of anengagement by notifying said engaging release means that a kensingtonlock has been inserted into said first kensington slot, and for notnotifying said engaging release means that said kensington lock has beeninserted into said second kensington slot; and (k) second notificationmeans for inhibiting release of an engagement by notifying said engagingrelease means that a kensington lock has been inserted into said firstkensington slot, and for not notifying said engaging release means thatsaid kensington lock has been inserted into said second kensington slot.12. A portable electronic apparatus comprising: (a) a main body; (b) afirst locking portion provided on the outer wall of said main body; (c)a second locking portion provided on the outer wall of said main body;(d) first theft prevention means for setting said main body to a firstsecurity mode when a locking member, for locking said main body to adesired peripheral object, is inserted into said first locking portion;and (e) second theft prevention means for setting said main body to asecond security mode which differs from said first security mode, whensaid locking member is inserted into said second locking portion.
 13. Aportable electronic apparatus comprising: (a) a main body; (b) a firstkensington slot provided on the outer wall of said main body; (c) asecond kensington slot provided on the outer wall of said main body; (d)first theft prevention means for setting said main body to a firstsecurity mode when a kensington lock is inserted into said firstkensington slot; and (e) second theft prevention means for setting saidmain body to a second security mode being different from said firstsecurity mode, when said kensington lock is inserted into said secondkensington slot.
 14. A docking unit for mounting a portable computercomprising: (a) a main body; (b) a mounting portion, for mounting aportable computer thereon; (c) a docking connector provided at anelevated location on said mounting portion for an electrical connectionwith said portable computer on said mounting portion; (d) engaging meansfor engaging with said portable computer mounted on said mountingportion; (e) ejecting means, provided on said mounting portion, to bevertically projected and retracted, such that said ejecting means isvertically projected to raise said portable computer mounted on saidmounting portion, for removal from said docking connector; (f) ejectinginstruction means used by a user to instruct ejection of said mountedportable computer; (g) notification means for, in response to a user'soperation of said ejecting instruction means, releasing said engagingmeans and extending said ejecting means vertically upward; and (h)retracting prevention means for preventing said ejecting means whenelevated from descending and being retracted into said mounting portion.15. The docking unit for a portable computer according to claim 14,wherein said retracting prevention means includes means for preventingretraction against a weight of said portable computer.